Manual activation of cooling fans

I would like to be able to activate my cooling fans manually from inside with a switch. The tempsensor must still work, however I would like to overide it when I am traviling slowly in game parks and up rough steep mountain passes. Any wiring experts know were to apply power without interfering with the electrical system?

unplugging the temp sensor activates the fans, so if you could use a switch to do this it's possible.

although i'm not sure what other affects this could have on the running ie. would it make the engine compensate by over fuelling etc........

oops, it's a gaylander, I withdraw

Take one of the temp sensor wires off, extend it back into the cab, connect to one of the pins on a switch, then connect the switch via another wire back to the removed contact on the temp sensor. When the switch is closed it will allow the temp sensor to run normally, when its open it will override the temp sensor and activate the fans. Simples!

JustinSA said:

I would like to be able to activate my cooling fans manually from inside with a switch. The tempsensor must still work, however I would like to overide it when I am traviling slowly in game parks and up rough steep mountain passes. Any wiring experts know were to apply power without interfering with the electrical system?

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Depends on the age of it! Early ones were relay controlled so will be easy! Later ones are controlled by the fan control unit for variable speed! Not so easy, but with a bit of thought I'm sure it can be done!
Ps ECM won't like temp sensor idea


DD

Good idea but will it not cause my engine managment to overfuel ?

Oh yes my landy is a 99 model 1.8i

JustinSA said:

Good idea but will it not cause my engine managment to overfuel ?

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Only 1 way to find out!

JustinSA said:

Good idea but will it not cause my engine managment to overfuel ?

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Yes it'll cock it right up!


DD

99 model year is relay controlled, so you can just use a switch another relay and splice a second feed into the fans! Or figure out how to switch the original relay which is what I'd try and do!


DD

Diesel Do said:

99 model year is relay controlled, so you can just use a switch another relay and splice a second feed into the fans! Or figure out how to switch the original relay which is what I'd try and do!


DD

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To switch the original would be easy, just find the 12v relay switch feed and splice into that, add a switch and an ignition live to the switch and job done.

JustinSA said:

I would like to be able to activate my cooling fans manually from inside with a switch. The tempsensor must still work, however I would like to overide it when I am traviling slowly in game parks and up rough steep mountain passes. Any wiring experts know were to apply power without interfering with the electrical system?

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My fans are perfectly adequate in 35+degreesC mountain-climbing off-road in the Balkans. They thrash away and the temp on my OBD readout has never been above 94degrees yet.

I cannot see what benefit one would obtain by manually overriding the system - assuming of course that the system is working correctly.

Have you had overheating problems? If so, how do you expect a manual over-ride to cool things better?

Singvogel.

mick 1986 said:

To switch the original would be easy, just find the 12v relay switch feed and splice into that, add a switch and an ignition live to the switch and job done.

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Its switched by the ECM so its most likely earth switching! Don't forget if you put 12v up an ECM earth you can blow it up that's why I suggested the other method as you don't run that risk!


DD

Singvogel said:

My fans are perfectly adequate in 35+degreesC mountain-climbing off-road in the Balkans. They thrash away and the temp on my OBD readout has never been above 94degrees yet.

I cannot see what benefit one would obtain by manually overriding the system - assuming of course that the system is working correctly.

Have you had overheating problems? If so, how do you expect a manual over-ride to cool things better?

Singvogel.

Click to expand...

I'm inclined to agree but mines never left the uk


DD

Diesel Do said:

Its switched by the ECM so its most likely earth switching! Don't forget if you put 12v up an ECM earth you can blow it up that's why I suggested the other method as you don't run that risk!


DD

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That's a fair point. In that case a second relay wired in parallel to the original with both outputs connected would be the best way.

No I have not had any heating issues however some of our parks have very thick soft sand and when outside temp is close to 38 39 sometimes 40degrees c things get way to hot under the bonnet so my plan is to keep the temp down from the start. It gets so hot sometimes under the bonnet you can smell the dirt on the splash plate starting to burn!

I have to have the A/C compressor overhauled as it is leaking doing that on Tuesday

When oft road I run the air con which runs the fans. I do this if it's hot, or the engine is hot. Easy option and you don't risk playing with the temp sensor which is also used for engine calcs. If putting a second control to the fans, make sure you don't bugger the control circuit from the fan computer. Yep they has a fan computer which is driven from engine computer. Enigne compueter controls the fan speed via fan computer.